Pregnancy Calculator
Calculate your due date, conception date, and view important pregnancy milestones.
Key Dates
| Conception Date: | – |
| Due Date: | – |
| Current Week: | – |
| First Trimester: | – |
| Second Trimester: | – |
| Third Trimester: | – |
Current Pregnancy Stage
Calculate your pregnancy to see your current stage information
Your Pregnancy Timeline
About Pregnancy & Due Dates
Pregnancy is a term used to describe a woman’s state over a time period (~9 months) during which one or more offspring develops inside of a woman. Childbirth usually occurs approximately 38 weeks after conception, or about 40 weeks after the last menstrual period. The World Health Organization defines a normal pregnancy term to last between 37 and 42 weeks.
During a person’s first OB-GYN visit, the doctor will usually provide an estimated date (based on a sonogram) at which the child will be born, or due date. Alternatively, the due date can also be estimated based on a person’s last menstrual period.
While the due date can be estimated, the actual length of pregnancy depends on various factors, including age, length of previous pregnancies, and weight of the mother at birth. Studies have shown that fewer than 4% of births occur on the exact due date, 60% occur within a week of the due date, and almost 90% occur within two weeks of the due date.
Pregnancy Detection
Pregnancy can be detected either by using pregnancy tests or by the woman herself noticing a number of symptoms, including a missed menstrual period, increased basal body temperature, fatigue, nausea, and increased frequency of urination.
Pregnancy tests involve the detection of hormones that serve as biomarkers for pregnancy and include clinical blood or urine tests that can detect pregnancy from six to eight days after fertilization.
Pregnancy Management
Medication
Taking certain medications during pregnancy can have lasting effects on the fetus. In the U.S., drugs are classified into categories A, B, C, D, and X by the Food and Drug Administration (FDA) based on potential benefits vs. fetal risks. A person that is pregnant should consult their doctor regarding any medications they plan to use during their pregnancy.
Weight gain
Weight gain is a largely inevitable and necessary aspect of pregnancy that varies between people. It affects many aspects of fetal development, such as the weight of the baby, the placenta, extra circulatory fluid, and its fat and protein stores. While the values vary between women, the Institute of Medicine recommends an overall pregnancy weight gain of 25-35 pounds for women who are considered “normal” weight (BMI 18.5-24.9), 28-40 pounds for those considered underweight (BMI < 18.5), 15-25 pounds for those considered overweight (BMI 25-29.9), and 11-20 pounds for those considered obese (BMI > 30).
Exercise
Studies indicate that aerobic exercise during pregnancy helps to improve or maintain physical fitness as well as possibly decreasing the risk of C-sections. The American College of Obstetricians and Gynecologists suggests that given an uncomplicated pregnancy, fetal injuries are unlikely to occur as a result of exercise.
Nutrition
Nutrition during pregnancy is particularly important for the health of the mother and baby. Pregnancy requires different nutritional considerations than a person would have in a non-pregnant state due to increased energy and specific micronutrient requirements. Pregnant women should consult their doctors and/or dietitian to help determine the best course of action for their own specific needs.
1. Jukic, AM, Baird, DD, Weinberg, CR, et al. 2013. “Length of human pregnancy and contributors to its natural variation.” Human Reproduction 28(10): 2848-55.
2. Moore, Keith. 2015. “How accurate are ‘due dates’?” BBC, February 3, 2015.
3. Institute of Medicine. 2009. “Weight Gain During Pregnancy: Reexamining the Guidelines.” National Academies Press.