Period or Pregnancy Symptoms: Am I Pregnant or PMS-ing?

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The road to pregnancy is often full of false alarms. Why? Because many early pregnancy symptoms (cramps, cravings) are quite similar to the symptoms before your period -- and the fact that the signs are different for every woman only adds to the confusion. 

That said, as a general rule, there are subtle differences between pregnancy and garden-variety PMS that can help you suss out which one you're dealing with. Here are a few signs that you may have a baby on board, and how these symptoms differ from a period:

  • Breast pain that lasts for weeks.

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    While having tender, swollen breasts is also a sign you could be on the brink of getting your period, with pregnancy that pain and discomfort is typically more extreme and lasts longer, too. "With a period, breast pain lasts just a few days, and once menses start, the pain is markedly reduced because progesterone levels are dropping," says Dr. Robert Atlas, OB/GYN, chair of the Department of Obstetrics and Gynecology at Mercy Medical Center. "With pregnancy, the progesterone continues to rise. I've seen some women complain of breast tenderness for a good part of the first trimester."

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  • Light spotting for just a couple days.

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    "Many pregnant women experience light spotting, which happens as the embryo implants itself in the endometrial lining," says Dr. Atlas. "But the spotting will typically be light and taper off in a couple days. Some women mistake that for their period when it's actually a pregnancy." So how to tell the difference? Periods are characterized by a much heavier and longer flow, lasting up to a week. 

  • Cramps that refuse to quit.

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    While cramps are a common symptom of both periods and pregnancy, "with a period, cramping is going to last a couple days during the menses," says Dr. Atlas. "Classically speaking, with pregnancy it will go on for a longer period of time, for weeks to months." 

  • Sleepiness or fatigue.

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    PMS has its share of misery-inducing symptoms, and extreme fatigue is generally not one of them. "There's a marked increase in fatigue in women who are pregnant than is ever related to menses. We see a huge increase in fatigue in newly pregnant women," says Dr. Atlas. "During her first pregnancy, my wife was sleeping a lot when she came home from work."

  • Nausea and vomiting.

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    Probably your clearest sign you're preggers is good old morning sickness. "If a woman's period is just late, usually there is no nausea and vomiting," says Dr. Daniel Roshan, a board-certified high-risk pregnancy maternal fetal medicine ob-gyn in New York. By comparison, 70 percent of pregnant women experience vomiting in the first trimester, says Dr. Atlas.

  • Strange food cravings or aversions.

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    While it's true that PMS may compel some women to eat sweets or some other indulgence, it's nothing compared to cravings and aversions experienced by pregnant women. "For them, the differences in their sense of smell and taste can be really strong," says Dr. Atlas. "I've heard of women who are vegetarians who crave meat and will become meat eaters at some point during the pregnancy. Or they may suddenly have an aversion to some food or smell." Some may experience pica, a condition where they crave things of no nutritional value, like corn starch or clay -- definitely not your typical reaction to PMS.

  • Of course, if you suspect you could be pregnant, there's no need to stay in the dark about it.

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    Take a pregnancy test or make an appointment with your doctor as soon as possible to clear up the confusion and plan accordingly.

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