How To Properly Read and Use an IVF Calculator

Dr. Randy Morris

How To Properly Read and Use an IVF Calculator

Dr. Randy Morris

If you are going through IVF, one of the most exciting parts of the process is learning about when your due date might be if the IVF cycle is successful. Calculating a due date for IVF is slightly different than calculating a due date for natural conception - fortunately, it is actually more precise. Below, we will take a look at how you can properly use an IVF calculator.

What a Due Date Means

A due date is simply the most likely date for the baby to be born. However, the baby is the one who will decide when it is time to be born. In the absence of complications, babies can be healthy and full-term when born as early as 37 weeks and as late as 42 weeks. Traditionally, due dates are calculated as being 40 weeks from the first day of the woman's last menstrual period (LMP). On average, ovulation occurs about 2 weeks from that date, which means that when a woman is said to be 25 weeks pregnant, the baby was conceived 23 weeks ago, and so on. Because there is variation in the length of the menstrual cycle, calculating the due date in this way is not an exact science. In some cases, the woman may be unsure of the date of her LMP. Fetal measurements on ultrasound can be used to estimate the due date in such cases. Fetal measurements are most accurate in the first trimester, because growth is fairly uniform at that time.

How IVF Affects Due Dates

The use of IVF can actually make due date calculation more precise, because the exact date that the egg was fertilized is known and the stage of the embryo at the time it is placed into the uterus is know. If you are transferring fresh (non-frozen) embryos, simply substitute the date of the egg retrieval for the ovulation date in any due date calculator. If frozen embryos were used, it is important to know how many days the embryos were cultured in the laboraotry before they were placed into the uterus. For example, a blastocyst transfer uses an embryo that was cultured for five days. If the embryo transfer was on the 15th, subtracting five days will give the "imaginary" day of conception. You would use the 10th as the day of ovulation. IVF also comes with an increased chance of having multiple pregnancies, especially twins. Because space in the womb is limited, each additional baby reduces the due date significantly. For twins, reaching 37 weeks is typically a good goal, and most babies born as early as 35 weeks have very good outcomes.



Using an IVF Calculator

If you are interested in IVF and in how to use an IVF due date calendar, Dr. Randy Morris would be happy to hear from you. To schedule your consultation today, please click below and enter your information or call IVF1 at (630) 357-6540.