Month six

We’ve all heard of it: women falling pregnant without having a clue, carrying on their daily lives without being aware of their growing babies. But how is this really possible? And could it happen to you?

“I didn’t know I was pregnant!”

Reality TV show I Didn’t Know I W as Pregnant would have us believe that every second women giving birth had no clue they were pregnant until it came time to push. In fact, it’s far less common: “In 30 years of private practice, I’ve only seen it once,” comments Dr Tobie de Villiers, a gynaecologist/obstetrician practising from Mediclinic Panorama in Cape Town. But not knowing you’re pregnant for the first half (or more) of pregnancy can, and does, happen for a few reasons.

CONTINUED BLEEDING

Bleeding in the first 12 weeks – called implantation bleeds – can be mistaken for a period. Dr JP du Buisson, a gynaecologist/ obstetrician, who also practices from Mediclinic Panorama, stresses that it’s important to remember that bleeding doesn’t always equal menstruation. He points out that implantation bleeding is usually a light spotting and therefore different from a normal period.

IRREGULAR PERIODS

Some women have irregular periods for reasons ranging from stress to being underweight, to having diabetes, polycystic ovarian disorder or a thyroid disorder. “So they don’t think it’s strange when they don’t have their period,” explains Dr de Villiers.

FALSE NEGATIVES

Human chorionic gonadotropin (hCG) is the hormone produced by the placenta after implantation of the embryo (six to 12 days after fertilisation). Increased hCG levels are normally a sure sign you’re pregnant, which is why this is what’s tested for in home pregnancy tests (urine) and, more accurately, blood tests. However, a very early home pregnancy test may produce a false negative, because hCG levels aren’t yet detectable. Dr de Villiers points out that although this isn’t too common, it’s always best to re-take a pregnancy test one week after a negative home test result. Another less common reason for a false negative on a home pregnancy test is that your foetus may be producing low levels of hCG. A blood test shows the true result, as it detects smaller traces of hCG than urine tests.

POLYCYSTIC OVARIAN DISORDER

A women with polycystic ovarian disorder (PCOS) will probably have irregular periods or no period at all; plus, she may believe she’s infertile because it’s more difficult – but not impossible – for her to get pregnant. In addition, PCOS can cause bloating, weight gain and pelvic pain, so it’s possible to mistake pregnancy symptoms for these.

NO TELL-TALE SIGNS

Many women first get a clue they’re pregnant from morning sickness, tiredness and/or hunger cravings. But with normal or low hCG levels, you may not experience any of these symptoms. On top of that, low hCG levels have been linked to low-weight babies who may not “show” for many weeks – and small babies tend to be less active, so kicks may not be felt. Add all of this to a false negative home pregnancy test and it’s easy to see why low hCG pregnancies can go undetected. But the more common reason for not detecting pregnancy is being overweight and therefore not noticing belly growth, according to Dr de Villiers. This is closely followed by being in denial. He says this usually happens when either the mother or the father has been told that they’re infertile.

DR DE VILLIERS POINTS OUT THAT ALTHOUGH THIS ISN’T TOO COMMON, IT’S ALWAYS BEST TO RE-TAKE A PREGNANCY TEST ONE WEEK AFTER A NEGATIVE HOME TEST RESULT. ANOTHER LESS COMMON REASON FOR A FALSE NEGATIVE ON A HOME PREGNANCY TEST IS THAT YOUR FOETUS MAY BE PRODUCING LOW LEVELS OF HCG.