The pregnancy is actually 10 months

How long does a pregnancy last?

It's a straight shot answer. How long does a pregnancy last? Well, nine months. Every child knows that. In fact, that's not entirely correct. "In general, pregnancy lasts ten lunar months, i.e. ten months of 28 days each. A lunar month is a lunar month and is used for the original calculation of the length of pregnancy," explains Robert Hundegger, gynecologist and senior physician at the Mistelbach State Hospital.

So the counting starts from the first day of the last menstrual period. According to this method, pregnancy lasts exactly 280 days, which is 40 weeks - of which a woman is actually only 38 weeks pregnant. "The fertilization of an egg does not take place until the end of the second week. That is why you have to deduct the first two weeks of pregnancy," explains gynecologist Agnes Hofer from Hollabrunn, who knows that many women only notice pregnancy when they feel sick in the morning. "But there are also pregnant women who do not show any of these symptoms. Women can suffer from nausea during pregnancy and experience no such symptoms with their next child," said Hofer.

Come to the world

The due date of a baby is calculated using the so-called Naegele rule. For example, in a 28-day cycle, seven days and a year are added from the first day of the last menstrual period and then three months are deducted. The result gives the expected due date of the child. "With a regular cycle, when 28 days pass between bleeds, it's a safe calculation." says gynecologist Robert Hundegger.

However, there are women who have a very irregular cycle, which makes it more difficult to predict. In these cases, the status of pregnancy can be determined with an ultrasound scan. In the first few weeks, the length of pregnancy can be deduced from the size of the embryo. "The due date can be determined based on the length of the child's crown and rump. If you measure the baby from head to buttocks, you can assign the body length to a specific week of pregnancy," explains gynecologist Agnes Hofer.

However, this method only works up to the 14th week, as all babies develop in the same way during this period. After that, the development of each individual child is different. "If the patient does not find out about her pregnancy until later, the child's cerebellum can also be measured in the ultrasound and thus the week of pregnancy can be determined," explains Hofer.

The time in your stomach

The length of a pregnancy can also depend on the age of the mother. "Pregnancy complications occur particularly in older women. These can make it necessary to induce labor prematurely or have a caesarean section," says Robert Hundegger. "The older, the higher the risk of suffering complications such as incontinence, high blood pressure or gestational diabetes during pregnancy," explains Hundegger.

The length of pregnancy is also documented in the mother-child pass. The duration is specified here with completed weeks and expired days of the current week. If a woman is 27 weeks and four days pregnant, it is noted in the mother-child pass as 27 + 4 weeks gestation (week of pregnancy). The first few weeks of pregnancy are the most uncertain in terms of miscarriages and complications. "In the eleventh or twelfth week, the risk of suffering a miscarriage is already lower," explains Hofer.

The percentage of babies that are actually born on the predicted due date is, however, rather low: "Only about five percent are born on the planned day," says Hundegger. Because when exactly the contractions start is ultimately determined by the child. "The international standard says that you shouldn't wait longer than ten days after the due date," explains gynecologist Hofer. Then the doctor will decide whether childbirth needs to be initiated. (Selma Tahirovic, January 26, 2018)