The luteal phase length can be longer or shorter. An LP shorter than 10 days is considered deficient in progesterone and is unable to maintain a pregnancy. There are measures to take to increase the LP, such as hormone therapy and/or herbal and vitamin supplements. No matter what day a woman ovulates, she can always tell approximately what day her menstrual cycle will begin, or what day to take a pregnancy test.
If pregnancy is the goal, it’s extremely important to have intercourse around the time of ovulation, preferably right before or during ovulation. Sometimes a woman’s body can gear up to ovulation- releasing all the right hormones and stress will halt the process. Vacations, moving, company or anything that causes undo stress can delay ovulation until the woman is at peace and relaxed again. The role of hormones combined with the woman’s state of health – i.e. sick or stressed, determines when and if ovulation occurs.
Sometimes ovulation does occur on day 14, but this is by far not the rule. Because the different elements that bring about ovulation can be varied or interrupted, it’s safe to say that ovulation can occur at any point in the cycle and not the day 14 that so many people once believed. Regardless of when ovulation occurs remember that the egg will only live 12 to 24 hours. The window of opportunity for conception to occur is very narrow indeed.