If you are temporarily unable to participate in physical activities at your sport centre (health problems, pregnancy, etc.), here's how you can suspend your subscription.
If you are unable to partake in physical activities for a limited time due to medical or professional reasons, check your contract for a clause which authorises the temporary suspension of your subscription.
Check your contract for whom you need to address the supporting documentation to (the centre and/or its insurer, for example) and contact them, making sure to send your suspension request with acknowledgment of receipt. Always keep a copy!. The date of the letter’s reception will begin the suspension period. Your contract may require you to continue paying the subscription fee during this period. Review all of the clauses in the contract in order to avoid any bad surprises.
If your contract doesn’t allow for a suspension, quote the Unfair Terms Commission (“Commission des Clauses Abusives”) in your letter as it advises that all contracts contain a clause permitting “an extension of the contract period, without additional fees, for the consumer temporarily restricted from benefiting from sport club services due to reasons relating to their state of health or professional activities” (Recommendation no. 87-03 concerning contracts offered by for-profit sport clubs of the CCA).
You can find a pattern for your recommended letter in French on the website of the National Institute for Consumption ("Institut National de la Consommation").