Fertility Abbreviations and TTC Glossary

Online TTC communities grew on message boards with character limits and fast-moving daily threads. Short codes let people share updates quickly: a single line like "12 DPO BFN" conveys cycle day context, testing timing, and result.

Medical letters use different acronyms, often Latin-derived or technical. IVF, IUI, and FSH appear in clinic notes. Overlap between slang and medicine is partial. CD means cycle day in forums but rarely in hospital correspondence.

Learning both layers helps you navigate apps, support groups, and appointments without misreading advice meant for a different stage or diagnosis.

BFP means big fat positive, forum slang for a positive pregnancy test. BFN means big fat negative. The phrases are informal but widely understood in English-speaking TTC spaces.

HPT means home pregnancy test. POAS means pee on a stick, jokingly describing taking an HPT. FRER refers to First Response Early Result, a sensitive brand often discussed in early testing threads.

Evap or evaporation line describes a colourless or grey mark that appears after the test window, not a true positive. See evaporation lines on pregnancy tests for how to tell the difference.

CD means cycle day, counted from the first day of full menstrual bleeding as day one. If your period starts on Monday, that Monday is CD1.

DPO means days past ovulation. If you ovulated on a Sunday, the following Monday is 1 DPO. Many people test around 10 to 14 DPO when hCG may be detectable.

AF means aunt flo, slang for menstrual period. When someone writes "AF arrived", their period started and the cycle ended without pregnancy.

O day means ovulation day. Follicular phase runs from CD1 to O day; luteal phase runs from O day until the next period or positive test.

TWW or 2WW means the two-week wait between ovulation and when a reliable pregnancy test can be taken. Emotionally it is often the hardest part of the cycle.

LP means luteal phase, the post-ovulation portion of the cycle when progesterone rises. LP length is often twelve to sixteen days. Shorter luteal phases sometimes concern charting enthusiasts, though clinical significance varies.

Spotting before AF may be logged as IB by some posters, short for implantation bleeding, though most spotting has other causes. Read progesterone and pregnancy for luteal phase context.

OPK means ovulation predictor kit, detecting luteinising hormone (LH) surge before ovulation. A positive OPK suggests ovulation may follow within about twenty-four to thirty-six hours.

CB means Clearblue, a brand of digital or line-based OPKs. SM means stretchy mucus or sometimes sperm meets egg in other contexts; context usually clarifies.

CM means cervical mucus. EWCM means egg white cervical mucus, fertile mucus that stretches between fingers and helps sperm travel. Watery or creamy mucus appears at other cycle phases.

BBT means basal body temperature, taken on waking before getting out of bed. A sustained rise often confirms ovulation retrospectively. BBT charting cannot predict ovulation in advance but validates timing after the fact.

TTC means trying to conceive. TTA means trying to avoid pregnancy. TTA/TTC threads in apps separate fertile tracking goals.

DH, DW, DP, and DS/DD mean dear husband, dear wife, dear partner, dear son, dear daughter. Forum conventions for privacy.

Rainbow baby refers to a baby born after pregnancy loss. Sunshine baby may mean a child born before a loss. These terms carry emotional weight in loss communities.

FTM and STM sometimes mean first-time mum or second-time mum in parenting contexts; verify meaning in each post because abbreviations overlap across topics.

IVF means in vitro fertilisation: eggs retrieved, fertilised in the laboratory, and embryos transferred to the uterus. IVF bypasses fallopian tubes and allows embryo selection.

IUI means intrauterine insemination: washed sperm placed into the uterus around ovulation. Less invasive and costly than IVF for some diagnoses.

ICSI means intracytoplasmic sperm injection, a laboratory technique injecting one sperm into an egg, often used when sperm count or motility is severely low during IVF.

FET means frozen embryo transfer, using embryos previously frozen rather than fresh from a retrieval cycle. Freeze-all cycles store all embryos before transfer.

ER means egg retrieval, the procedure collecting eggs during IVF. ET means embryo transfer. Beta or beta hCG is a blood pregnancy test measuring hCG after transfer or timed intercourse.

Antagonist and agonist protocols describe different IVF medication schedules to prevent premature ovulation during stimulation. Your clinic names the specific drugs used.

OHSS means ovarian hyperstimulation syndrome, a complication of fertility drugs where ovaries become swollen and fluid shifts occur. Severity ranges from mild bloating to hospital care.

PUPO means pregnant until proven otherwise, forum optimism between transfer or ovulation and testing. Medically, pregnancy is confirmed by rising hCG, not assumption alone.

FSH means follicle stimulating hormone, often measured on cycle day two or three to assess ovarian reserve. High FSH may correlate with lower reserve. See FSH levels and pregnancy.

LH means luteinising hormone, surging before ovulation and detected by OPKs. AMH means anti-Müllerian hormone, a blood marker estimating ovarian reserve.

E2 means oestradiol, a form of oestrogen. P4 or prog means progesterone, supporting the luteal phase and early pregnancy.

hCG means human chorionic gonadotrophin, the hormone pregnancy tests detect. TSH means thyroid stimulating hormone, relevant when thyroid and fertility overlap.

PCOS means polycystic ovary syndrome, a common cause of irregular ovulation. Endo means endometriosis, tissue similar to the womb lining growing outside the uterus.

MF infertility or MFI means male factor infertility. Unexplained IF means infertility without identified cause after standard testing.

RPL means recurrent pregnancy loss, multiple miscarriages warranting investigation. CP means chemical pregnancy, a very early loss after positive hCG but before ultrasound confirmation.

MC means miscarriage. EP means ectopic pregnancy, implantation outside the uterus requiring urgent care.

EDD or EDD means estimated due date. LMP means last menstrual period, used to date pregnancy before ultrasound.

US or u/s means ultrasound. NT scan means nuchal translucency screening in early pregnancy. Anatomy scan refers to the detailed mid-pregnancy ultrasound.

NIPT means non-invasive prenatal testing, screening fetal DNA from maternal blood. CVS and amnio mean chorionic villus sampling and amniocentesis, diagnostic genetic tests.

Live birth, term birth, and preterm abbreviations appear in research more than daily forums but surface in clinic leaflets.

BD means baby dance, forum euphemism for intercourse timed around fertility. Some find it twee; others use it to discuss timing without explicit language.

DTD means doing the deed, similar euphemism. LL means low libido, sometimes logged when TTC stress affects frequency.

Triphasic chart describes a BBT pattern with a second rise in the luteal phase; enthusiasts debate predictive value for pregnancy.

Coverline on BBT charts separates follicular from luteal temperatures. Charting platforms calculate it automatically when you log daily readings.

Same abbreviations mean different things outside fertility. FTMO in trading forums means something entirely unrelated. Always read context.

Medical acronyms in posts are not diagnoses. Someone sharing high FSH values without context may have a different age and history than you.

British and American spellings differ: oestrogen versus estrogen, fertilisation versus fertilization. ClearLine uses British English; some forums mix both.

Avoid applying one poster's protocol to yourself. Clomid, letrozole, and trigger shots require prescription and monitoring.

Clinic letters prefer full terms with abbreviations in brackets on first use: in vitro fertilisation (IVF). They rarely use BFP or AF.

Semen analysis reports use WHO reference terminology: concentration, motility, morphology. Forum shorthand like "low swimmers" means poor motility informally.

Bring a glossary like this to appointments if acronyms blur together. Asking for plain language is always appropriate.

NHS preconception guidance uses accessible wording for people starting to try, though specialist letters may still feel dense without decoding support.

DPT means days past transfer in IVF contexts, analogous to DPO after ovulation. Testing too early produces false negatives whether you count DPO or DPT.

Wondfo and easy@home are inexpensive strip test brands discussed online alongside premium FRER tests. Sensitivity thresholds differ by brand.

Indent line means a faint manufacturing mark that can resemble early positive. Always read within the test window specified in instructions.

See how to read a pregnancy test and very faint lines for visual interpretation beyond abbreviations.

Start with CD, DPO, OPK, BFP, BFN, and TWW if you track cycles online. Add IVF-related terms when treatment begins. Layer hormone abbreviations when blood results arrive.

Save clinic paperwork with a note translating unfamiliar acronyms. Photos of whiteboards after consultations fade from memory quickly.

Share this glossary with partners or family if they support your journey but find forum posts confusing. Common language reduces miscommunication during stressful cycles.

• BFP/BFN: positive/negative pregnancy test (forum slang)
• CD: cycle day from first day of period
• DPO: days past ovulation
• OPK: ovulation predictor kit detecting LH surge
• TWW: two-week wait after ovulation before reliable testing
• IVF/IUI/ICSI: assisted reproduction techniques
• FSH/AMH/LH: hormones used in fertility testing
• PCOS/Endo: common conditions affecting conception

Clomid is shorthand for clomifene citrate, an oral ovulation induction drug. Letrozole is another oral option sometimes labelled Femara by brand name in posts.

Gonal-F, Menopur, and Puregon are injectable FSH brand names used in IVF stimulation. Cetrotide and Orgalutran are GnRH antagonists preventing premature ovulation during stim cycles.

Trigger shots use hCG brand names such as Ovidrel or Pregnyl to mimic LH surge and mature eggs before retrieval. Luveris adds LH activity in some protocols for poor responders.

Progesterone support after transfer may appear as pessaries, Crinone gel, or Lubion injections abbreviated in patient logs as P4 support.

TikTok and Instagram fertility creators sometimes invent new abbreviations weekly. IF community, TTC journey, and fertility warrior appear as hashtags rather than clinical codes.

Line eyes means scrutinising faint test lines before the official read window, often debated in photo threads. Tweakers edit contrast on images, which can create false positives psychologically.

Dusty uterus is informal slang for luteal phase or endometrial readiness discussions without standard medical definition. Treat colourful phrases as emotional venting unless tied to a diagnosis.

When in doubt, ask the poster what they mean rather than assuming a medical acronym matches your clinic letter.

Beyond definitions, grouping terms by when you encounter them helps. Early trying focuses on CD, OPK, EWCM, BD, BFP, and BFN. Treatment cycles add ER, ET, FET, beta, and stim medication names.

Loss and rainbow terminology deserves sensitivity. Not everyone uses CP, MC, or RPL labels publicly. Follow the language people choose for their experiences.

Apps like ClearLine may use plain language in the interface while communities retain shorthand. Both serve different purposes: clarity versus speed.

Return to this glossary whenever a new abbreviation appears in a thread or letter. Fertility vocabulary expands as your journey progresses from tracking to treatment to pregnancy care.

Print or bookmark sections relevant to your stage rather than memorising every entry. Treatment abbreviations matter most once stimulation begins; daily forum slang matters most while tracking natural cycles.

Partners who do not browse forums may still encounter acronyms on clinic whiteboards or prescription labels. Sharing plain-language translations reduces confusion during stressful appointment days.

HFEA means the Human Fertilisation and Embryology Authority, the UK regulator for licensed fertility clinics. You may see HFEA numbers on clinic websites confirming licence status.

WTD can mean withdrawal of treatment consent forms in clinic paperwork contexts. PGT-A and PGT-M mean preimplantation genetic testing for aneuploidy or monogenic conditions during IVF embryo selection.

Surrogacy discussions use IP for intended parents and SM for surrogate mother in legal summaries. UK surrogacy law is complex; abbreviations in law firm guides differ from medical clinic forms.

Understanding regulatory acronyms helps you verify you are at a licensed centre when comparing advertised egg freezing or IVF packages.

Keep a personal cheat sheet of abbreviations your clinic uses in blood forms and portal messages. Software systems sometimes auto-generate labels patients never see explained verbally.

ClearLine articles use plain language in guides while respecting that community shorthand will still appear in comments and support groups you may join alongside reading here.

When abbreviations appear in your hospital portal, search this page or ask your nurse coordinator for plain English definitions before assuming the worst.