It's a symptom that's hard to ignore; a sharp, almost electric shooting pain that fires down into your vagina without warning, causing many to yelp out from the shock. While there is no research into how many women experience this painful pregnancy phenomenon colloquially dubbed "lightning crotch," anecdotal evidence suggests it's more common that not.
"The true cause of lightning pain is unknown, however the most popular theory is that the weight of the baby compresses on nerves that run to the vagina, causing a jolt of pain," Amy Gildner, a physiotherapist at West End Mamas in Toronto with more than four years experience as a pelvic physiotherapist, told HuffPost Canada.
"The vaginal opening leads to the pelvic floor, which is just a collection of muscles that sit in your pelvic bones," she said. "These muscles act as a 'hammock' to support everything inside of us. However, the pelvic floor often cannot accommodate the sudden weight gain in pregnancy, and these muscles become overworked and strained, which can ultimately lead to pelvic pain."
Passing often just as quickly as it came, lightning pain can also occur in the rectum and pelvis, not just the vagina. And, while it is a common symptom of pregnancy, women without children can also experience it. If pregnancy is not a factor, lightning pain may be due to period pain, abdominal cramping, ovarian cyst pain, or other causes.
While Gildner notes that vaginal pain in pregnancy is common, it doesn't have to be normal.
"Pain with pregnancy is definitely common, but there is no reason to live like that," she said. "I think that if anyone has any sort of pain, they should go see a healthcare practitioner."
Maddi Reid told HuffPost Canada that she experienced lightning pain midway through her 37th week of pregnancy right up until she gave birth three weeks later. The mom of one from Port Hope, Ont. mainly experienced lightning pain at night while laying down, saying the pain often woke her up from sleep because it was so intense.
"My doctor was no help," she said. "I heard from other moms that warm baths or tonic water before bed might help. I did some research and read about yoga, and different forms of chiropractic and massage, but for me, nothing worked," Reid said.
One thing that Reid found did ease the pain was to walk up and down the stairs.
Tanya Wakelin, also of Port Hope, Ont., had a much more intense experience with lightning crotch, with the first pains happening when she was around five months pregnant.
"It was scary at first because it was my first pregnancy, I had no idea what was going on," she told HuffPost Canada. "It felt like bending your finger so far back that you beg for mercy. And then in a flash it was gone. I'd even screech in public because it was so unexpected, never knowing when it was going to sneak up."
The mother of one said that as her pregnancy went on the pain lasted for longer and had more of a pressure sensation to it, with the end of her pregnancy being the worst.
Wakelin mentioned the pain to her midwife, who explained that what she was experiencing was lightning pain. The midwife told her that there unfortunately wasn't much in the way of treatment, but that she could try a bath to relax and see if that helped the pain.
Like Reid, Wakelin found that nothing really helped her symptoms, and she just learned to live with the pain.
"It was easier when I knew what the stabbing pain was. I would know it would end eventually," she said.
While lightning pain is just one cause of vaginal pain during pregnancy, Gildner says that round ligament strain, varicose veins, and movement of the baby could all be to blame as well. While the discomfort should subside once baby is born, expectant mothers have options when it comes to treating vaginal pains during pregnancy.
"Maintaining good posture and increasing flexibility can help prevent lightning crotch, as well as pelvic floor physiotherapy to release any tight musculature internally that may be pre-disposing nerve compression," Gildner said. "Further along in pregnancy, belts that lift the belly will alleviate some of the load placed on the nerves, and thus help to relieve any pain."
Wakelin encourages women who experience lightning pain to talk to their partners about it, and to explain how debilitating the pain can be.
"It was nice to have a hubby who embraced the nickname and understood when I'd stop walking in a store all of a sudden and just say 'lightening crotch'."
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