Your period is a bit late. But just when you begin to wonder if you might be pregnant, the familiar cramps in your lower tummy start. Time for painkillers, chocolate, a big glass of wine and a hot water bottle. Or not..? It might be wise to wait with the painkillers and the wine until the menstrual blood really starts flowing, as for many women early pregnancy can feel just like menstruation cramps.
Cramps: PMS, menstrual or implantation?
Implantation cramps occur when the fertilised egg implants itself into the uterus lining. Usually, this implantation happens between 7 and 12 days after the ovulation; around the time you’d expect any PMS-symptoms. Normally your menstruation starts between 12 and 16 days after your ovulation, so when you’ve got a short cycle the implantation cramps might actually coincide with when you’d expect your period to start. Sometimes the implantation cramps are accompanied by light bleeding or spotting, which, indeed, might also resemble the start of your menstrual flow. More similarities: breast swelling, fatigue, food cravings and mood swings are both PMS-symptoms and a sign of (early) pregnancy.
There are also a couple of differences: implantation cramps are usually milder than menstrual cramps and only last for 1 to 3 days, whereas most menstrual or PMS-related cramps unfortunately last longer and are more intense. Another contrast: the colour and duration of the bleeding. In the beginning of your period, menstrual blood is usually pink, changing to red when your flow is heaviest, whereas the light bleeding that might happen during implantation has a much lighter or even a brown colour. Plus: a normal menstruation lasts 5 to 7 days whereas implantation bleeding only lasts a day or two.
Stretching of the uterus
Also in the weeks after the implantation you can feel mild cramps in the lower back and lower tummy that resemble period pain. That’s because when you’re pregnant, your uterus stretches and expands in preparation for the growing baby, causing lower abdominal cramping. And when you’re on your period, your uterus contracts itself to expel its lining. Logical that for most women, these uterus movements feel very alike. Some women even describe their early pregnancy as ‘feeling like my period could start any minute now’.
And yes, even later in their pregnancy women can feel pain that resembles period pain. Lower back pain, for example, can be caused by the added weight and pressure of the pregnancy. And in the second trimester, the round ligament, a muscle in the lower abdomen that supports the uterus, gets stretched which can cause cramps and pelvic discomfort. By then however, your missed periods, nausea, vomiting, ever-growing tummy and perhaps an ultrasound or two will probably have confirmed that you’re expecting a baby instead of a really late period.
Moral of the story: when in doubt and your menstruation is a bit late, get a pregnancy test.