Fertility and menstrual cycle my husband and i have been trying to have a baby. i was supposed to start my cycle on the 12th of jan but never did. i have taken two pregnancy tests about two weeks apart since and they have both come out negative. why ha

The : The most likely reason you have not had your period is that you did not ovulate. This could be a reason why you are not getting pregnant. A simple way to find out what is happening now is to have blood drawn for the hormones: e2, p4, hcg. This should be done by a fertility doctor who can make a decision about what to do right now with the information. It may be time to start an infertility evaluation.

The : The diagnosis of pregnancy is a very common question for women and also on this forum. Let me give you a couple of facts about your contraceptive and timing and conception. You probably are not pregnant based on the facts that i will add below. I cannot say why you cycle is late but you may not have ovulated this cycle and that cannot account for a delayed menses. A normal menstrual cycle consists of two parts: the follicular phase and the luteal phase. The ideal menstrual cycle is 28 days and both the follicular and luteal phases are 14 days long. The follicular phase is when the follicle (cyst containing an egg) grows and produces the hormone estrogen, which causes the lining (endometrium) to thicken. The luteal phase is the second half of the cycle after ovulation (release of and egg) when the corpus luteum (new name for the cyst after ovulation) produces Progesterone that makes the lining of the uterus receptive to the embryo, if you had fertilization of the egg. Ovulation occurs on day 14 (of an ideal cycle) and after release from the follicle, the egg can be fertilized for only about 24 hours at most (experience from ivf). The egg is fertilized at the end of the tube nearest the ovary. The fertilized egg (embryo) then takes about 3 days to reach the endometrium. The embryo continues to grow in the lining for about 2 days and then implants (attaches to the endometrium) about 5-6 days after ovulation. The implanted embryo then grows and starts to secrete hcg. The level of HCG in the blood stream rises enough to be measured about 10-11 days after ovulation. Most menstrual cycles are not ideal and the thus timing is not known for many women. Perhaps the most consistent part of the cycle is to expect ovulation about 14 days before menses (again, this is not perfect). A few days can make a big difference between a pregnancy test being negative or positive. Home tests are not as sensitive as blood tests. The symptoms of pregnancy typically will not be evident until the HCG level is high enough to measure in the blood stream. All of this information is variable and I have had several situations of proven pregnancy that defies explanation based on timing. Nevertheless, this data is helpful to try and explain when testing and symptoms should occur. Blood pregnancy tests are the most accurate and are positive about 12 days after ovulation. Home urine tests are less accurate but usually correct. I have had patients with negative urine tests and very positive blood tests. We require all our ivf patients to get a blood test before stopping their hormones because of this fact, for example. I hope this information makes sense and helps you understand where you are in the cycle and pregnancy (if you did become pregnant). Best wishes.